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    <title>html5 programming</title>
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    <h1>H1:html5 programming</h1>
    <h2>H2:html5 programming</h2>
    <h3>H3:html5 programming</h3>
    <h4>H4:html5 programming</h4>
    <h5>H5:html5 programming</h5>
    <h6>H6:html5 programming</h6>

    <p>html5 programming</p>
    <p>html5 programming</p>

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        details: html5 programming
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       <p>
        details: html5 programming
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            html5
        </summary>
        <p>
            details: html5 programming
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